In this paper a relaxation theory, proposed several years ago for plasmaswhere a single dominant mode is present, is revisited. The solutions of therelated eigenvalue problem are numerically calculated and discussed. Althoughthese solutions are very rich and can reproduce well the magnetic fieldsmeasured in experiments, there is no manner within the theory to determine thedominant helicity, which is a free parameter in the model. To find thepreferred helicity in the system, we propose to minimize the distance of therelaxed state from another state which is constructed as a two regiongeneralization of the Taylor relaxation model allowing current jumps. It isfound that this comparison is able to predict the observed scaling with theaspect ratio and reversal parameter for the dominant mode in the Single Helicalstates.
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